class A:
    i = 10

    def sum(self):
        return self.getI() + 10

    def sum1(self):
        return self.i + 10

    def getI(self):
        return self.i


class B(A):
    i = 20

    # def sum(self):
    #     return self.getI() + 20

    def getI(self):
        return self.i

    # def sum1(self):
    #     return self.i + 10


b = B()
print(b.sum())
print(b.sum1())
